IGST AMENDMENT SEC 12 SUB SEC (8)

As per the proviso inserted in Amendment Act 32 of 2018 , & the same was effective by Notification 1/2019 IGST Act

"Provided that where the transportation of goods is to a place outside India,
the place of supply shall be the place of destination of such goods.".

Hence the Courier company is liable to charge IGST , even though the sender (Supplier) is same state , & you cant avail ITC on same .

But .....

In this regard, we can hope clarification from the Board otherwise there will be problem regarding determination of place of supply which may further create confusion in availing ITC whether on CGST/SGST or IGST. Sooner the clarification, less the problems for assessees.